Prior to his short stay at Zynga, Van Natta, 41, had brief stops
at both Facebook and MySpace.

Zynga is expected to make its trading debut
after the U.S. Thanksgiving holiday. The company looks to
raise up to $1 billion in its initial public offering. SharesPost, a secondary trading market, lists
the value of Zynga's shares at around $20.

Van Natta will remain on Zynga's board of
directors. Brad Feld, an investor in Zynga with
Foundry Group, is also leaving Zynga's
board of directors.